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Quantization of Space and Time in 3 and in 4 Space-time Dimensions

G. 't Hooft
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Abstract

The fact that in Minkowski space, space and time are both quantized does not have to be introduced as a new postulate in physics, but can actually be derived by combining certain features of General Relativity and Quantum Mechanics. This is demonstrated first in a model where particles behave as point defects in 2 space dimensions and 1 time, and then in the real world having 3+1 dimensions. The mechanisms in these two cases are quite different, but the outcomes are similar: space and time form a (non-cummutative) lattice. These notes are short since most of the material discussed in these lectures is based on two earlier papers by the same author (gr-qc/9601014 and gr-qc/9607022), but the exposition given in the end is new.

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G. 't Hooft. 1996-08-16. Quantization of Space and Time in 3 and in 4 Space-time Dimensions. https://arxiv.org/abs/gr-qc/9608037

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